Attention-deficit/hyperactivity disorder is a chronic disorder that results in substantial short-term and long-term impairment for affected children and their families. Traditional behavioral parent training (BPT) has been identified as an efficacious treatment for children with ADHD. Not all families, however, derive equal benefits from BPT. Research has indicated that specific characteristics of the family predict a poorer response to BPT. In particular, single-mother households are more likely to experience such difficulty. The aim of the research program is to enhance BPT to increase participation, engagement, and outcomes for single mothers of children diagnosed with ADHD. The novel parent training format will be investigated and compared to a BPT program in a randomized clinical trial investigating the most efficacious means of engaging, retaining, and improving outcomes for single-mothers of children with ADHD in behavioral parent training.